Determination of amatoxins in different tissues and development stages of Amanita exitialis.

BACKGROUND: Mushroom poisoning is the main cause of human death by food poisoning in China. Most lethal mushrooms belong to the Amanita genus, whose amatoxins are responsible for the death of humans. Amanita exitialis is a lethal white mushroom commonly found in Guangdong Province, China. In this study the contents and distribution of the major amatoxins in different tissues and development stages of A. exitialis were systematically analysed.
RESULTS: The amatoxin contents and distribution in six different mushroom tissues of A. exitialis were analysed by reverse phase high-performance liquid chromatography. The highest concentrations of amatoxins were found in the gills and pileus, followed by the stipe and annulus, with the lowest concentrations in the volva and spores. Further analysis of mushrooms in different development stages showed that the amatoxin content was relatively high and steady during early development, reached its peak when the fruit body was in the vigorous growth stage and then decreased sharply when the mushroom entered its mature stage. Furthermore, the α-amanitin/β-amanitin ratio varied significantly in different tissues but remained constant within a specific tissue throughout development.
CONCLUSION: The contents and distribution of amatoxins in different tissues and development stages of A. exitialis are markedly different. The distribution of α-amanitin and β-amanitin varies in different tissues but remains constant throughout development.